package nz.ac.waikato.cs.stemmer;

import java.util.*;

/**
 *    LovinsStemmer.java
 *    Copyright (C) 2001 Eibe Frank
 *
 *    This program is free software; you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation; either version 2 of the License, or
 *    (at your option) any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
public class LovinsStemmer {

	/** Enters C version compatibility mode if set to true (emulates
      features of the original C implementation that are inconsistent
      with the algorithm as described in Lovins's paper) */
	private final static boolean m_CompMode = false;

	/** The hash tables containing the list of endings. */
	private final static HashMap<String,String> m_l11 = new HashMap<String,String>();
	private final static HashMap<String,String> m_l10 = new HashMap<String,String>();
	private final static HashMap<String,String> m_l9 = new HashMap<String,String>();
	private final static HashMap<String,String> m_l8 = new HashMap<String,String>();
	private final static HashMap<String,String> m_l7 = new HashMap<String,String>();
	private final static HashMap<String,String> m_l6 = new HashMap<String,String>();
	private final static HashMap<String,String> m_l5 = new HashMap<String,String>();
	private final static HashMap<String,String> m_l4 = new HashMap<String,String>();
	private final static HashMap<String,String> m_l3 = new HashMap<String,String>();
	private final static HashMap<String,String> m_l2 = new HashMap<String,String>();
	private final static HashMap<String,String> m_l1 = new HashMap<String,String>();

	static {

		m_l11.put("alistically", "B");
		m_l11.put("arizability", "A");
		m_l11.put("izationally", "B");

		m_l10.put("antialness", "A");
		m_l10.put("arisations", "A");
		m_l10.put("arizations", "A");
		m_l10.put("entialness", "A");

		m_l9.put("allically", "C");
		m_l9.put("antaneous", "A");
		m_l9.put("antiality", "A");
		m_l9.put("arisation", "A");
		m_l9.put("arization", "A");
		m_l9.put("ationally", "B");
		m_l9.put("ativeness", "A");
		m_l9.put("eableness", "E");
		m_l9.put("entations", "A");
		m_l9.put("entiality", "A");
		m_l9.put("entialize", "A");
		m_l9.put("entiation", "A");
		m_l9.put("ionalness", "A");
		m_l9.put("istically", "A");
		m_l9.put("itousness", "A");
		m_l9.put("izability", "A");
		m_l9.put("izational", "A");

		m_l8.put("ableness", "A");
		m_l8.put("arizable", "A");
		m_l8.put("entation", "A");
		m_l8.put("entially", "A");
		m_l8.put("eousness", "A");
		m_l8.put("ibleness", "A");
		m_l8.put("icalness", "A");
		m_l8.put("ionalism", "A");
		m_l8.put("ionality", "A");
		m_l8.put("ionalize", "A");
		m_l8.put("iousness", "A");
		m_l8.put("izations", "A");
		m_l8.put("lessness", "A");
		
		m_l7.put("ability", "A");
		m_l7.put("aically", "A");
		m_l7.put("alistic", "B");
		m_l7.put("alities", "A");
		m_l7.put("ariness", "E");
		m_l7.put("aristic", "A");
		m_l7.put("arizing", "A");
		m_l7.put("ateness", "A");
		m_l7.put("atingly", "A");
		m_l7.put("ational", "B");
		m_l7.put("atively", "A");
		m_l7.put("ativism", "A");
		m_l7.put("elihood", "E");
		m_l7.put("encible", "A");
		m_l7.put("entally", "A");
		m_l7.put("entials", "A");
		m_l7.put("entiate", "A");
		m_l7.put("entness", "A");
		m_l7.put("fulness", "A");
		m_l7.put("ibility", "A");
		m_l7.put("icalism", "A");
		m_l7.put("icalist", "A");
		m_l7.put("icality", "A");
		m_l7.put("icalize", "A");
		m_l7.put("ication", "G");
		m_l7.put("icianry", "A");
		m_l7.put("ination", "A");
		m_l7.put("ingness", "A");
		m_l7.put("ionally", "A");
		m_l7.put("isation", "A");
		m_l7.put("ishness", "A");
		m_l7.put("istical", "A");
		m_l7.put("iteness", "A");
		m_l7.put("iveness", "A");
		m_l7.put("ivistic", "A");
		m_l7.put("ivities", "A");
		m_l7.put("ization", "F");
		m_l7.put("izement", "A");
		m_l7.put("oidally", "A");
		m_l7.put("ousness", "A");
		
		m_l6.put("aceous", "A");
		m_l6.put("acious", "B");
		m_l6.put("action", "G");
		m_l6.put("alness", "A");
		m_l6.put("ancial", "A");
		m_l6.put("ancies", "A");
		m_l6.put("ancing", "B");
		m_l6.put("ariser", "A");
		m_l6.put("arized", "A");
		m_l6.put("arizer", "A");
		m_l6.put("atable", "A");
		m_l6.put("ations", "B");
		m_l6.put("atives", "A");
		m_l6.put("eature", "Z");
		m_l6.put("efully", "A");
		m_l6.put("encies", "A");
		m_l6.put("encing", "A");
		m_l6.put("ential", "A");
		m_l6.put("enting", "C");
		m_l6.put("entist", "A");
		m_l6.put("eously", "A");
		m_l6.put("ialist", "A");
		m_l6.put("iality", "A");
		m_l6.put("ialize", "A");
		m_l6.put("ically", "A");
		m_l6.put("icance", "A");
		m_l6.put("icians", "A");
		m_l6.put("icists", "A");
		m_l6.put("ifully", "A");
		m_l6.put("ionals", "A");
		m_l6.put("ionate", "D");
		m_l6.put("ioning", "A");
		m_l6.put("ionist", "A");
		m_l6.put("iously", "A");
		m_l6.put("istics", "A");
		m_l6.put("izable", "E");
		m_l6.put("lessly", "A");
		m_l6.put("nesses", "A");
		m_l6.put("oidism", "A");
		
		m_l5.put("acies", "A");
		m_l5.put("acity", "A");
		m_l5.put("aging", "B");
		m_l5.put("aical", "A");
		if (!m_CompMode) {
			m_l5.put("alist", "A");
		}
		m_l5.put("alism", "B");
		m_l5.put("ality", "A");
		m_l5.put("alize", "A");
		m_l5.put("allic", "b");
		m_l5.put("anced", "B");
		m_l5.put("ances", "B");
		m_l5.put("antic", "C");
		m_l5.put("arial", "A");
		m_l5.put("aries", "A");
		m_l5.put("arily", "A");
		m_l5.put("arity", "B");
		m_l5.put("arize", "A");
		m_l5.put("aroid", "A");
		m_l5.put("ately", "A");
		m_l5.put("ating", "I");
		m_l5.put("ation", "B");
		m_l5.put("ative", "A");
		m_l5.put("ators", "A");
		m_l5.put("atory", "A");
		m_l5.put("ature", "E");
		m_l5.put("early", "Y");
		m_l5.put("ehood", "A");
		m_l5.put("eless", "A");
		if (!m_CompMode) {
			m_l5.put("elily", "A");
		} else {
			m_l5.put("elity", "A");
		}
		m_l5.put("ement", "A");
		m_l5.put("enced", "A");
		m_l5.put("ences", "A");
		m_l5.put("eness", "E");
		m_l5.put("ening", "E");
		m_l5.put("ental", "A");
		m_l5.put("ented", "C");
		m_l5.put("ently", "A");
		m_l5.put("fully", "A");
		m_l5.put("ially", "A");
		m_l5.put("icant", "A");
		m_l5.put("ician", "A");
		m_l5.put("icide", "A");
		m_l5.put("icism", "A");
		m_l5.put("icist", "A");
		m_l5.put("icity", "A");
		m_l5.put("idine", "I");
		m_l5.put("iedly", "A");
		m_l5.put("ihood", "A");
		m_l5.put("inate", "A");
		m_l5.put("iness", "A");
		m_l5.put("ingly", "B");
		m_l5.put("inism", "J");
		m_l5.put("inity", "c");
		m_l5.put("ional", "A");
		m_l5.put("ioned", "A");
		m_l5.put("ished", "A");
		m_l5.put("istic", "A");
		m_l5.put("ities", "A");
		m_l5.put("itous", "A");
		m_l5.put("ively", "A");
		m_l5.put("ivity", "A");
		m_l5.put("izers", "F");
		m_l5.put("izing", "F");
		m_l5.put("oidal", "A");
		m_l5.put("oides", "A");
		m_l5.put("otide", "A");
		m_l5.put("ously", "A");
		
		m_l4.put("able", "A");
		m_l4.put("ably", "A");
		m_l4.put("ages", "B");
		m_l4.put("ally", "B");
		m_l4.put("ance", "B");
		m_l4.put("ancy", "B");
		m_l4.put("ants", "B");
		m_l4.put("aric", "A");
		m_l4.put("arly", "K");
		m_l4.put("ated", "I");
		m_l4.put("ates", "A");
		m_l4.put("atic", "B");
		m_l4.put("ator", "A");
		m_l4.put("ealy", "Y");
		m_l4.put("edly", "E");
		m_l4.put("eful", "A");
		m_l4.put("eity", "A");
		m_l4.put("ence", "A");
		m_l4.put("ency", "A");
		m_l4.put("ened", "E");
		m_l4.put("enly", "E");
		m_l4.put("eous", "A");
		m_l4.put("hood", "A");
		m_l4.put("ials", "A");
		m_l4.put("ians", "A");
		m_l4.put("ible", "A");
		m_l4.put("ibly", "A");
		m_l4.put("ical", "A");
		m_l4.put("ides", "L");
		m_l4.put("iers", "A");
		m_l4.put("iful", "A");
		m_l4.put("ines", "M");
		m_l4.put("ings", "N");
		m_l4.put("ions", "B");
		m_l4.put("ious", "A");
		m_l4.put("isms", "B");
		m_l4.put("ists", "A");
		m_l4.put("itic", "H");
		m_l4.put("ized", "F");
		m_l4.put("izer", "F");
		m_l4.put("less", "A");
		m_l4.put("lily", "A");
		m_l4.put("ness", "A");
		m_l4.put("ogen", "A");
		m_l4.put("ward", "A");
		m_l4.put("wise", "A");
		m_l4.put("ying", "B");
		m_l4.put("yish", "A");
		
		m_l3.put("acy", "A");
		m_l3.put("age", "B");
		m_l3.put("aic", "A");
		m_l3.put("als", "b");
		m_l3.put("ant", "B");
		m_l3.put("ars", "O");
		m_l3.put("ary", "F");
		m_l3.put("ata", "A");
		m_l3.put("ate", "A");
		m_l3.put("eal", "Y");
		m_l3.put("ear", "Y");
		m_l3.put("ely", "E");
		m_l3.put("ene", "E");
		m_l3.put("ent", "C");
		m_l3.put("ery", "E");
		m_l3.put("ese", "A");
		m_l3.put("ful", "A");
		m_l3.put("ial", "A");
		m_l3.put("ian", "A");
		m_l3.put("ics", "A");
		m_l3.put("ide", "L");
		m_l3.put("ied", "A");
		m_l3.put("ier", "A");
		m_l3.put("ies", "P");
		m_l3.put("ily", "A");
		m_l3.put("ine", "M");
		m_l3.put("ing", "N");
		m_l3.put("ion", "Q");
		m_l3.put("ish", "C");
		m_l3.put("ism", "B");
		m_l3.put("ist", "A");
		m_l3.put("ite", "a");
		m_l3.put("ity", "A");
		m_l3.put("ium", "A");
		m_l3.put("ive", "A");
		m_l3.put("ize", "F");
		m_l3.put("oid", "A");
		m_l3.put("one", "R");
		m_l3.put("ous", "A");
		
		m_l2.put("ae", "A"); 
		m_l2.put("al", "b");
		m_l2.put("ar", "X");
		m_l2.put("as", "B");
		m_l2.put("ed", "E");
		m_l2.put("en", "F");
		m_l2.put("es", "E");
		m_l2.put("ia", "A");
		m_l2.put("ic", "A");
		m_l2.put("is", "A");
		m_l2.put("ly", "B");
		m_l2.put("on", "S");
		m_l2.put("or", "T");
		m_l2.put("um", "U");
		m_l2.put("us", "V");
		m_l2.put("yl", "R");
		m_l2.put("s\'", "A");
		m_l2.put("\'s", "A");
		
		m_l1.put("a", "A");
		m_l1.put("e", "A");
		m_l1.put("i", "A");
		m_l1.put("o", "A");
		m_l1.put("s", "W");
		m_l1.put("y", "B");	
	}

	/**
	 * Finds and removes ending from given word.
	 */
	private static String removeEnding(String word) {

		int length = word.length();
		int el = 11;

		while (el > 0) {
			if (length - el > 1) {
				String ending = word.substring(length - el);
				String conditionCode = null;
				switch (el) {
				case 11: conditionCode = m_l11.get(ending);
				break;
				case 10: conditionCode = m_l10.get(ending);
				break; 
				case 9: conditionCode = m_l9.get(ending);
				break;
				case 8: conditionCode = m_l8.get(ending);
				break;   
				case 7: conditionCode = m_l7.get(ending);
				break;   
				case 6: conditionCode = m_l6.get(ending);
				break;   
				case 5: conditionCode = m_l5.get(ending);
				break;   
				case 4: conditionCode = m_l4.get(ending);
				break;   
				case 3: conditionCode = m_l3.get(ending);
				break;   
				case 2: conditionCode = m_l2.get(ending);
				break;   
				case 1: conditionCode = m_l1.get(ending);
				break;   
				default:
				}
				if (conditionCode != null) {
					switch (conditionCode.charAt(0)) {
					case 'A':
						return word.substring(0, length - el);
					case 'B':
						if (length - el > 2) {
							return word.substring(0, length - el);
						}
						break;
					case 'C':
						if (length - el > 3) {
							return word.substring(0, length - el);
						}
						break;
					case 'D':
						if (length - el > 4) {
							return word.substring(0, length - el);
						}
						break;
					case 'E':
						if (word.charAt(length - el - 1) != 'e') {
							return word.substring(0, length - el);
						}
						break;
					case 'F':
						if ((length - el > 2) &&
								(word.charAt(length - el - 1) != 'e')) {
							return word.substring(0, length - el);
						}
						break;
					case 'G':
						if ((length - el > 2) &&
								(word.charAt(length - el - 1) == 'f')) {
							return word.substring(0, length - el);
						}
						break;
					case 'H':
						if ((word.charAt(length - el - 1) == 't') ||
								((word.charAt(length - el - 1) == 'l') &&
										(word.charAt(length - el - 2) == 'l'))) {
							return word.substring(0, length - el);
						}
						break;
					case 'I':
						if ((word.charAt(length - el - 1) != 'o') &&
								(word.charAt(length - el - 1) != 'e')) { 
							return word.substring(0, length - el);
						}
						break;
					case 'J':
						if ((word.charAt(length - el - 1) != 'a') &&
								(word.charAt(length - el - 1) != 'e')) { 
							return word.substring(0, length - el);
						}
						break;
					case 'K':
						if ((length - el > 2) &&
								((word.charAt(length - el - 1) == 'l') ||
										(word.charAt(length - el - 1) == 'i') ||
										((word.charAt(length - el - 1) == 'e') &&
												(word.charAt(length - el - 3) == 'u')))) {
							return word.substring(0, length - el);
						}
						break;
					case 'L':
						if ((word.charAt(length - el - 1) != 'u') &&
								(word.charAt(length - el - 1) != 'x') &&
								((word.charAt(length - el - 1) != 's') ||
										(word.charAt(length - el - 2) == 'o'))) {
							return word.substring(0, length - el);
						}
						break;
					case 'M':
						if ((word.charAt(length - el - 1) != 'a') &&
								(word.charAt(length - el - 1) != 'c') &&
								(word.charAt(length - el - 1) != 'e') &&
								(word.charAt(length - el - 1) != 'm')) {
							return word.substring(0, length - el);
						}
						break;
					case 'N':
						if ((length - el > 3) || 
								((length - el == 3) &&
										((word.charAt(length - el - 3) != 's')))) {
							return word.substring(0, length - el);
						}
						break;
					case 'O':
						if ((word.charAt(length - el - 1) == 'l') ||
								(word.charAt(length - el - 1) == 'i')) {
							return word.substring(0, length - el);
						}
						break;
					case 'P':
						if (word.charAt(length - el - 1) != 'c') {
							return word.substring(0, length - el);
						}
						break;
					case 'Q':
						if ((length - el > 2) &&
								(word.charAt(length - el - 1) != 'l') &&
								(word.charAt(length - el - 1) != 'n')) {
							return word.substring(0, length - el);
						}
						break;
					case 'R':
						if ((word.charAt(length - el - 1) == 'n') ||
								(word.charAt(length - el - 1) == 'r')) {
							return word.substring(0, length - el);
						}
						break;
					case 'S':
						if (((word.charAt(length - el - 1) == 'r') &&
								(word.charAt(length - el - 2) == 'd')) ||
								((word.charAt(length - el - 1) == 't') &&
										(word.charAt(length - el - 2) != 't'))) {
							return word.substring(0, length - el);
						}
						break;
					case 'T':
						if ((word.charAt(length - el - 1) == 's') ||
								((word.charAt(length - el - 1) == 't') &&
										(word.charAt(length - el - 2) != 'o'))) {
							return word.substring(0, length - el);
						}
						break;
					case 'U':
						if ((word.charAt(length - el - 1) == 'l') ||
								(word.charAt(length - el - 1) == 'm') ||
								(word.charAt(length - el - 1) == 'n') ||
								(word.charAt(length - el - 1) == 'r')) {
							return word.substring(0, length - el);
						}
						break;
					case 'V':
						if (word.charAt(length - el - 1) == 'c') {
							return word.substring(0, length - el);
						}
						break;
					case 'W':
						if ((word.charAt(length - el - 1) != 's') &&
								(word.charAt(length - el - 1) != 'u')) {
							return word.substring(0, length - el);
						}
						break;
					case 'X':
						if ((word.charAt(length - el - 1) == 'l') ||
								(word.charAt(length - el - 1) == 'i') ||
								((length - el > 2) &&
										(word.charAt(length - el - 1) == 'e') &&
										(word.charAt(length - el - 3) == 'u'))) {
							return word.substring(0, length - el);
						}
						break;
					case 'Y':
						if ((word.charAt(length - el - 1) == 'n') &&
								(word.charAt(length - el - 2) == 'i')) {
							return word.substring(0, length - el);
						}
						break;
					case 'Z':
						if (word.charAt(length - el - 1) != 'f') {
							return word.substring(0, length - el);
						}
						break;
					case 'a':
						if ((word.charAt(length - el - 1) == 'd') ||
								(word.charAt(length - el - 1) == 'f') ||
								(((word.charAt(length - el - 1) == 'h') &&
										(word.charAt(length - el - 2) == 'p'))) ||
										(((word.charAt(length - el - 1) == 'h') &&
												(word.charAt(length - el - 2) == 't'))) ||
												(word.charAt(length - el - 1) == 'l') ||
												(((word.charAt(length - el - 1) == 'r') &&
														(word.charAt(length - el - 2) == 'e'))) ||
														(((word.charAt(length - el - 1) == 'r') &&
																(word.charAt(length - el - 2) == 'o'))) ||
																(((word.charAt(length - el - 1) == 's') &&
																		(word.charAt(length - el - 2) == 'e'))) ||
																		(word.charAt(length - el - 1) == 't')) {
							return word.substring(0, length - el);
						}
						break;
					case 'b':
						if (m_CompMode) {
							if (((length - el == 3 ) &&
									(!((word.charAt(length - el - 1) == 't') &&
											(word.charAt(length - el - 2) == 'e') &&
											(word.charAt(length - el - 3) == 'm')))) ||
											((length - el > 3) &&
													(!((word.charAt(length - el - 1) == 't') &&
															(word.charAt(length - el - 2) == 's') &&
															(word.charAt(length - el - 3) == 'y') &&
															(word.charAt(length - el - 4) == 'r'))))) {
								return word.substring(0, length - el);
							}
						} else {
							if ((length - el > 2) &&
									(!((word.charAt(length - el - 1) == 't') &&
											(word.charAt(length - el - 2) == 'e') &&
											(word.charAt(length - el - 3) == 'm'))) &&
											((length - el < 4) ||
													(!((word.charAt(length - el - 1) == 't') &&
															(word.charAt(length - el - 2) == 's') &&
															(word.charAt(length - el - 3) == 'y') &&
															(word.charAt(length - el - 4) == 'r'))))) {
								return word.substring(0, length - el);
							}
						} 
						break;
					case 'c':
						if (word.charAt(length - el - 1) == 'l') {
							return word.substring(0, length - el);
						}
						break;
					default:
						throw new IllegalArgumentException("Fatal error.");
					}
				}
			}
			el--;
		}
		return word;
	}

	/**
	 * Recodes ending of given word.
	 */
	private static String recodeEnding(String word) {

		int lastPos = word.length() - 1;

		// Rule 1
		if (word.endsWith("bb") ||
				word.endsWith("dd") ||
				word.endsWith("gg") ||
				word.endsWith("ll") ||
				word.endsWith("mm") ||
				word.endsWith("nn") ||
				word.endsWith("pp") ||
				word.endsWith("rr") ||
				word.endsWith("ss") ||
				word.endsWith("tt")) {
			word = word.substring(0, lastPos);
			lastPos--;
		}

		// Rule 2
		if (word.endsWith("iev")) {
			word = word.substring(0, lastPos - 2).concat("ief");
		}

		// Rule 3
		if (word.endsWith("uct")) {
			word = word.substring(0, lastPos - 2).concat("uc");
			lastPos--;
		}

		// Rule 4
		if (word.endsWith("umpt")) {
			word = word.substring(0, lastPos - 3).concat("um");
			lastPos -= 2;
		}

		// Rule 5
		if (word.endsWith("rpt")) {
			word = word.substring(0, lastPos - 2).concat("rb");
			lastPos--;
		}

		// Rule 6
		if (word.endsWith("urs")) {
			word = word.substring(0, lastPos - 2).concat("ur");
			lastPos--;
		}

		// Rule 7
		if (word.endsWith("istr")) {
			word = word.substring(0, lastPos - 3).concat("ister");
			lastPos++;
		}

		// Rule 7a
		if (word.endsWith("metr")) {
			word = word.substring(0, lastPos - 3).concat("meter");
			lastPos++;
		}

		// Rule 8
		if (word.endsWith("olv")) {
			word = word.substring(0, lastPos - 2).concat("olut");
			lastPos++;
		}

		// Rule 9
		if (word.endsWith("ul")) {
			if ((lastPos - 2 < 0) ||
					((word.charAt(lastPos - 2) != 'a') &&
							(word.charAt(lastPos - 2) != 'i') &&
							(word.charAt(lastPos - 2) != 'o'))) {
				word = word.substring(0, lastPos - 1).concat("l");
				lastPos--;
			}
		}

		// Rule 10
		if (word.endsWith("bex")) {
			word = word.substring(0, lastPos - 2).concat("bic");
		}

		// Rule 11
		if (word.endsWith("dex")) {
			word = word.substring(0, lastPos - 2).concat("dic");
		}

		// Rule 12
		if (word.endsWith("pex")) {
			word = word.substring(0, lastPos - 2).concat("pic");
		}

		// Rule 13
		if (word.endsWith("tex")) {
			word = word.substring(0, lastPos - 2).concat("tic");
		}

		// Rule 14
		if (word.endsWith("ax")) {
			word = word.substring(0, lastPos - 1).concat("ac");
		}

		// Rule 15
		if (word.endsWith("ex")) {
			word = word.substring(0, lastPos - 1).concat("ec");
		}

		// Rule 16
		if (word.endsWith("ix")) {
			word = word.substring(0, lastPos - 1).concat("ic");
		}

		// Rule 17
		if (word.endsWith("lux")) {
			word = word.substring(0, lastPos - 2).concat("luc");
		}

		// Rule 18
		if (word.endsWith("uad")) {
			word = word.substring(0, lastPos - 2).concat("uas");
		}

		// Rule 19
		if (word.endsWith("vad")) {
			word = word.substring(0, lastPos - 2).concat("vas");
		}

		// Rule 20
		if (word.endsWith("cid")) {
			word = word.substring(0, lastPos - 2).concat("cis");
		}

		// Rule 21
		if (word.endsWith("lid")) {
			word = word.substring(0, lastPos - 2).concat("lis");
		}

		// Rule 22
		if (word.endsWith("erid")) {
			word = word.substring(0, lastPos - 3).concat("eris");
		}

		// Rule 23
		if (word.endsWith("pand")) {
			word = word.substring(0, lastPos - 3).concat("pans");
		}

		// Rule 24
		if (word.endsWith("end")) {
			if ((lastPos - 3 < 0) ||
					(word.charAt(lastPos - 3) != 's')) {
				word = word.substring(0, lastPos - 2).concat("ens");
			}
		}

		// Rule 25
		if (word.endsWith("ond")) {
			word = word.substring(0, lastPos - 2).concat("ons");
		}

		// Rule 26
		if (word.endsWith("lud")) {
			word = word.substring(0, lastPos - 2).concat("lus");
		}

		// Rule 27
		if (word.endsWith("rud")) {
			word = word.substring(0, lastPos - 2).concat("rus");
		}

		// Rule 28
		if (word.endsWith("her")) {
			if ((lastPos - 3 < 0) ||
					((word.charAt(lastPos - 3) != 'p') &&
							(word.charAt(lastPos - 3) != 't'))) {
				word = word.substring(0, lastPos - 2).concat("hes");
			}
		}

		// Rule 29
		if (word.endsWith("mit")) {
			word = word.substring(0, lastPos - 2).concat("mis");
		}

		// Rule 30
		if (word.endsWith("end")) {
			if ((lastPos - 3 < 0) ||
					(word.charAt(lastPos - 3) != 'm')) {
				word = word.substring(0, lastPos - 2).concat("ens");
			}
		}

		// Rule 31
		if (word.endsWith("ert")) {
			word = word.substring(0, lastPos - 2).concat("ers");
		}

		// Rule 32
		if (word.endsWith("et")) {
			if ((lastPos - 2 < 0) ||
					(word.charAt(lastPos - 2) != 'n')) {
				word = word.substring(0, lastPos - 1).concat("es");
			}
		}

		// Rule 33
		if (word.endsWith("yt")) {
			word = word.substring(0, lastPos - 1).concat("ys");
		}

		// Rule 34
		if (word.endsWith("yz")) {
			word = word.substring(0, lastPos - 1).concat("ys");
		}

		return word;
	}

	/**
	 * Returns the stemmed version of the given word.
	 * Word is converted to lower case before stemming.
	 * 
	 * @param word a string consisting of a single word
	 */
	public static String stem(String word) {

		if (word.length() > 2) {
			return recodeEnding(removeEnding(word.toLowerCase()));
		}
		return word.toLowerCase();
	}

	/**
	 * @param word
	 * @return Returns the ending
	 */
	public static String getEnding(String word) {
		String stem = removeEnding(word.toLowerCase());
		return word.substring(stem.length());
	}
	
	/**
	 * Stems everything in the given string. String
	 * is converted to lower case before stemming.
	 */
	public static String stemString(String str) {

		StringBuffer result = new StringBuffer();
		int start = -1;
		for (int j = 0; j < str.length(); j++) {
			char c = str.charAt(j);
			if (Character.isLetterOrDigit(c)) {
				if (start == -1) {
					start = j;
				}
			} else if (c == '\'') {
				if (start == -1) {
					result.append(c);
				}
			} else {
				if (start != -1) {
					result.append(stem(str.substring(start, j)));
					start = -1;
				}
				result.append(c);
			}
		}
		if (start != -1) {
			result.append(stem(str.substring(start, str.length())));
		}
		return result.toString();  
	}

	/**
	 * Stems text coming into stdin and writes it to stdout.
	 */
	public static void main(String[] ops) {

		try {
			int num;
			StringBuffer wordBuffer = new StringBuffer();
			while ((num = System.in.read()) != -1) {
				char c = (char)num;
				if (((num >= 'A') && (num <= 'Z')) ||
						((num >= 'a') && (num <= 'z'))) {
					wordBuffer.append(c);
				} else {
					if (wordBuffer.length() > 0) {
						System.out.print(LovinsStemmer.stem(wordBuffer.toString().
								toLowerCase()));
						wordBuffer = new StringBuffer();
					}
					System.out.print(c);
				}
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
}


